950 lines
30 KiB
C
950 lines
30 KiB
C
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/*
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* Copyright 2018-2021 NXP
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* All rights reserved.
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*
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*
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* SPDX-License-Identifier: BSD-3-Clause
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*/
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#include "fsl_puf.h"
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#include "fsl_clock.h"
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#include "fsl_common.h"
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#if !(defined(FSL_FEATURE_PUF_HAS_NO_RESET) && (FSL_FEATURE_PUF_HAS_NO_RESET > 0))
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#include "fsl_reset.h"
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#endif /* FSL_FEATURE_PUF_HAS_NO_RESET */
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/* Component ID definition, used by tools. */
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#ifndef FSL_COMPONENT_ID
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#define FSL_COMPONENT_ID "platform.drivers.puf"
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#endif
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/* RT6xx POWER CONTROL bit masks */
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#if defined(FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL) && (FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL > 0)
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#define PUF_PWRCTRL_CKDIS_MASK (0x4U)
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#define PUF_PWRCTRL_RAMINIT_MASK (0x8U)
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#define PUF_PWRCTRL_RAMPSWLARGEMA_MASK (0x10U)
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#define PUF_PWRCTRL_RAMPSWLARGEMP_MASK (0x20U)
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#define PUF_PWRCTRL_RAMPSWSMALLMA_MASK (0x40U)
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#define PUF_PWRCTRL_RAMPSWSMALLMP_MASK (0x80U)
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#endif
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#if defined(FSL_FEATURE_PUF_HAS_SRAM_CTRL) && (FSL_FEATURE_PUF_HAS_SRAM_CTRL > 0)
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#define DEFAULT_CKGATING 0x0u
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#define PUF_ENABLE_MASK 0xFFFFFFFEu
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#define PUF_ENABLE_CTRL 0x1u
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#else
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static void puf_wait_usec(volatile uint32_t usec, uint32_t coreClockFrequencyMHz)
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{
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SDK_DelayAtLeastUs(usec, coreClockFrequencyMHz * 1000000U);
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/* Instead of calling SDK_DelayAtLeastUs() implement delay loop here */
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// while (usec > 0U)
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// {
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// usec--;
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// number of MHz is directly number of core clocks to wait 1 usec.
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// the while loop below is actually 4 clocks so divide by 4 for ~1 usec
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// volatile uint32_t ticksCount = coreClockFrequencyMHz / 4u + 1u;
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// while (0U != ticksCount--)
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// {
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// }
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// }
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}
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#endif /* defined(FSL_FEATURE_PUF_HAS_SRAM_CTRL) && (FSL_FEATURE_PUF_HAS_SRAM_CTRL > 0) */
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static status_t puf_waitForInit(PUF_Type *base)
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{
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status_t status = kStatus_Fail;
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/* wait until status register reads non-zero. All zero is not valid. It should be BUSY or OK or ERROR */
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while (0U == base->STAT)
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{
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}
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/* wait if busy */
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while ((base->STAT & PUF_STAT_BUSY_MASK) != 0U)
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{
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}
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/* return status */
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if (0U != (base->STAT & (PUF_STAT_SUCCESS_MASK | PUF_STAT_ERROR_MASK)))
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{
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status = kStatus_Success;
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}
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return status;
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}
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static void puf_powerOn(PUF_Type *base, puf_config_t *conf)
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{
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#if defined(FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL) && (FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL > 0)
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/* RT6xxs */
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base->PWRCTRL = (PUF_PWRCTRL_RAM_ON_MASK | PUF_PWRCTRL_CK_DIS_MASK);
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base->PWRCTRL = (PUF_PWRCTRL_RAM_ON_MASK | PUF_PWRCTRL_CK_DIS_MASK | PUF_PWRCTRL_RAMINIT_MASK);
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base->PWRCTRL = (PUF_PWRCTRL_RAM_ON_MASK | PUF_PWRCTRL_RAMINIT_MASK);
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#elif defined(FSL_FEATURE_PUF_HAS_SRAM_CTRL) && (FSL_FEATURE_PUF_HAS_SRAM_CTRL > 0)
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/* LPCXpresso55s16 */
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conf->puf_sram_base->CFG |= PUF_ENABLE_CTRL;
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while (0U == (PUF_SRAM_CTRL_STATUS_READY_MASK & conf->puf_sram_base->STATUS))
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{
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}
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#else /* !FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL */
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/* LPCXpresso55s69 & LPCXpresso54S018 */
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base->PWRCTRL = PUF_PWRCTRL_RAMON_MASK;
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while (0U == (PUF_PWRCTRL_RAMSTAT_MASK & base->PWRCTRL))
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{
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}
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#endif /* FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL */
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}
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/*!
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* brief Powercycle PUF
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*
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* This function make powercycle of PUF.
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*
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* param base PUF peripheral base address
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* param conf PUF configuration structure
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* return Status of the powercycle operation.
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*/
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status_t PUF_PowerCycle(PUF_Type *base, puf_config_t *conf)
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{
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#if defined(FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL) && (FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL > 0)
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/* RT6xxs */
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uint32_t coreClockFrequencyMHz = conf->coreClockFrequencyHz / 1000000u;
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base->PWRCTRL = (PUF_PWRCTRL_RAM_ON_MASK | PUF_PWRCTRL_CK_DIS_MASK | PUF_PWRCTRL_RAMINIT_MASK); /* disable RAM CK */
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/* enter ASPS mode */
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base->PWRCTRL = (PUF_PWRCTRL_CK_DIS_MASK | PUF_PWRCTRL_RAMINIT_MASK); /* SLEEP = 1 */
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base->PWRCTRL = (PUF_PWRCTRL_RAMINIT_MASK); /* enable RAM CK */
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base->PWRCTRL = (PUF_PWRCTRL_RAMINIT_MASK | PUF_PWRCTRL_RAMPSWLARGEMA_MASK | PUF_PWRCTRL_RAMPSWLARGEMP_MASK |
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PUF_PWRCTRL_RAMPSWSMALLMA_MASK | PUF_PWRCTRL_RAMPSWSMALLMP_MASK); /* SLEEP=1, PSW*=1 */
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/* Wait enough time to discharge fully */
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puf_wait_usec(conf->dischargeTimeMsec * 1000u, conf->coreClockFrequencyHz / 1000000u);
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/* write PWRCTRL=0x38. wait time > 1 us */
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base->PWRCTRL = (PUF_PWRCTRL_RAMINIT_MASK | PUF_PWRCTRL_RAMPSWLARGEMA_MASK |
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PUF_PWRCTRL_RAMPSWLARGEMP_MASK); /* SLEEP=1. PSWSMALL*=0. PSWLARGE*=1. */
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puf_wait_usec(1, coreClockFrequencyMHz);
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/* write PWRCTRL=0x8. wait time > 1 us */
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base->PWRCTRL = PUF_PWRCTRL_RAMINIT_MASK; /* SLEEP=1. PSWSMALL*=0. PSWLARGE*=0 */
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puf_wait_usec(1, coreClockFrequencyMHz);
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base->PWRCTRL = (PUF_PWRCTRL_CK_DIS_MASK | PUF_PWRCTRL_RAMINIT_MASK);
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base->PWRCTRL = (PUF_PWRCTRL_RAM_ON_MASK | PUF_PWRCTRL_CK_DIS_MASK | PUF_PWRCTRL_RAMINIT_MASK);
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base->PWRCTRL = (PUF_PWRCTRL_RAM_ON_MASK | PUF_PWRCTRL_RAMINIT_MASK);
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/* Generate INITN low pulse */
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base->PWRCTRL = (PUF_PWRCTRL_RAM_ON_MASK | PUF_PWRCTRL_CK_DIS_MASK | PUF_PWRCTRL_RAMINIT_MASK);
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base->PWRCTRL = (PUF_PWRCTRL_RAM_ON_MASK | PUF_PWRCTRL_CK_DIS_MASK);
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base->PWRCTRL = PUF_PWRCTRL_RAM_ON_MASK;
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#elif defined(FSL_FEATURE_PUF_HAS_SRAM_CTRL) && (FSL_FEATURE_PUF_HAS_SRAM_CTRL > 0)
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/* LPCXpresso55s16 */
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conf->puf_sram_base->CFG &= PUF_ENABLE_MASK;
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#else
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/* LPCXpresso55s69 & LPCXpresso54S018 */
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base->PWRCTRL = 0x0u;
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while (0U != (PUF_PWRCTRL_RAMSTAT_MASK & base->PWRCTRL))
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{
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}
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/* Wait enough time to discharge fully */
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puf_wait_usec(conf->dischargeTimeMsec * 1000u, conf->coreClockFrequencyHz / 1000000u);
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#endif
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#if !(defined(FSL_FEATURE_PUF_HAS_NO_RESET) && (FSL_FEATURE_PUF_HAS_NO_RESET > 0))
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/* Reset PUF and reenable power to PUF SRAM */
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RESET_PeripheralReset(kPUF_RST_SHIFT_RSTn);
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#endif /* FSL_TEATURE_PUF_HAS_NO_RESET */
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puf_powerOn(base, conf);
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return kStatus_Success;
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}
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/*!
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* brief Sets the default configuration of PUF
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*
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* This function initialize PUF config structure to default values.
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*
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* param conf PUF configuration structure
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*/
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void PUF_GetDefaultConfig(puf_config_t *conf)
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{
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#if defined(FSL_FEATURE_PUF_HAS_SRAM_CTRL) && (FSL_FEATURE_PUF_HAS_SRAM_CTRL > 0)
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/* LPCXpresso55s16 */
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conf->puf_sram_base = PUF_SRAM_CTRL;
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/* Default configuration after reset */
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conf->CKGATING = DEFAULT_CKGATING; /* PUF SRAM Clock Gating */
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#endif /* FSL_FEATURE_PUF_HAS_SRAM_CTRL */
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conf->dischargeTimeMsec = KEYSTORE_PUF_DISCHARGE_TIME_FIRST_TRY_MS;
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conf->coreClockFrequencyHz = CLOCK_GetFreq(kCLOCK_CoreSysClk);
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return;
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}
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/*!
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* brief Initialize PUF
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*
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* This function enables power to PUF block and waits until the block initializes.
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*
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* param base PUF peripheral base address
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* param conf PUF configuration structure
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* return Status of the init operation
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*/
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status_t PUF_Init(PUF_Type *base, puf_config_t *conf)
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{
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status_t status = kStatus_Fail;
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#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
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CLOCK_EnableClock(kCLOCK_Puf);
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#endif
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#if !(defined(FSL_FEATURE_PUF_HAS_NO_RESET) && (FSL_FEATURE_PUF_HAS_NO_RESET > 0))
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/* Reset PUF */
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RESET_PeripheralReset(kPUF_RST_SHIFT_RSTn);
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#endif /* FSL_FEATURE_PUF_HAS_NO_RESET */
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#if defined(FSL_FEATURE_PUF_HAS_SRAM_CTRL) && (FSL_FEATURE_PUF_HAS_SRAM_CTRL > 0)
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/* Set configuration for SRAM */
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conf->puf_sram_base->CFG |= PUF_SRAM_CTRL_CFG_CKGATING(conf->CKGATING);
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#endif /* FSL_FEATURE_PUF_HAS_SRAM_CTRL */
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/* Enable power to PUF SRAM */
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puf_powerOn(base, conf);
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/* Wait for peripheral to become ready */
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status = puf_waitForInit(base);
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/* In case of error or enroll or start not allowed, do power-cycle */
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/* First try with shorter discharge time, if then it also fails try with longer time */
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/* conf->dischargeTimeMsec = KEYSTORE_PUF_DISCHARGE_TIME_FIRST_TRY_MS; */
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if ((status != kStatus_Success) || (0U == (base->ALLOW & (PUF_ALLOW_ALLOWENROLL_MASK | PUF_ALLOW_ALLOWSTART_MASK))))
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{
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(void)PUF_PowerCycle(base, conf);
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status = puf_waitForInit(base);
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}
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/* In case of error or enroll or start not allowed, do power-cycle with worst discharge timing */
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if ((status != kStatus_Success) || (0U == (base->ALLOW & (PUF_ALLOW_ALLOWENROLL_MASK | PUF_ALLOW_ALLOWSTART_MASK))))
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{
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conf->dischargeTimeMsec = KEYSTORE_PUF_DISCHARGE_TIME_MAX_MS;
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(void)PUF_PowerCycle(base, conf);
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status = puf_waitForInit(base);
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}
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return status;
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}
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/*!
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* brief Denitialize PUF
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*
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* This function disables power to PUF SRAM and peripheral clock.
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*
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* param base PUF peripheral base address
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* param conf PUF configuration structure
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*/
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void PUF_Deinit(PUF_Type *base, puf_config_t *conf)
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{
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#if defined(FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL) && (FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL > 0)
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/* RT6xxs */
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base->PWRCTRL = (PUF_PWRCTRL_RAM_ON_MASK | PUF_PWRCTRL_CK_DIS_MASK | PUF_PWRCTRL_RAMINIT_MASK); /* disable RAM CK */
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/* enter ASPS mode */
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base->PWRCTRL = (PUF_PWRCTRL_CK_DIS_MASK | PUF_PWRCTRL_RAMINIT_MASK); /* SLEEP = 1 */
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base->PWRCTRL = PUF_PWRCTRL_RAMINIT_MASK; /* enable RAM CK */
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base->PWRCTRL = (PUF_PWRCTRL_RAMINIT_MASK | PUF_PWRCTRL_RAMPSWLARGEMA_MASK | PUF_PWRCTRL_RAMPSWLARGEMP_MASK |
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PUF_PWRCTRL_RAMPSWSMALLMA_MASK | PUF_PWRCTRL_RAMPSWSMALLMP_MASK); /* SLEEP=1, PSW*=1 */
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puf_wait_usec(conf->dischargeTimeMsec * 1000u, conf->coreClockFrequencyHz / 1000000u);
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#elif defined(FSL_FEATURE_PUF_HAS_SRAM_CTRL) && (FSL_FEATURE_PUF_HAS_SRAM_CTRL > 0)
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/* LPCXpresso55s16 */
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conf->puf_sram_base = PUF_SRAM_CTRL;
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conf->puf_sram_base->CFG &= PUF_ENABLE_MASK;
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#else /* !FSL_FEATURE_PUF_PWR_HAS_MANUAL_SLEEP_CONTROL */
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/* LPCXpresso55s69 & LPCXpresso54S018 */
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base->PWRCTRL = 0x00u;
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puf_wait_usec(conf->dischargeTimeMsec * 1000u, conf->coreClockFrequencyHz / 1000000u);
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#endif
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#if !(defined(FSL_FEATURE_PUF_HAS_NO_RESET) && (FSL_FEATURE_PUF_HAS_NO_RESET > 0))
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RESET_SetPeripheralReset(kPUF_RST_SHIFT_RSTn);
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#endif /* FSL_FEATURE_PUF_HAS_NO_RESET */
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#if !(defined(FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL) && FSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL)
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CLOCK_DisableClock(kCLOCK_Puf);
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#endif
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}
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/*!
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* brief Enroll PUF
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*
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* This function derives a digital fingerprint, generates the corresponding Activation Code (AC)
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* and returns it to be stored in an NVM or a file. This step needs to be
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* performed only once for each device. This function may be permanently disallowed by a fuse.
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*
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* param base PUF peripheral base address
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* param[out] activationCode Word aligned address of the resulting activation code.
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* param activationCodeSize Size of the activationCode buffer in bytes. Shall be 1192 bytes.
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* return Status of enroll operation.
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*/
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status_t PUF_Enroll(PUF_Type *base, uint8_t *activationCode, size_t activationCodeSize)
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{
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status_t status = kStatus_Fail;
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uint32_t *activationCodeAligned = NULL;
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register uint32_t temp32 = 0;
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/* check that activation code buffer size is at least 1192 bytes */
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if (activationCodeSize < PUF_ACTIVATION_CODE_SIZE)
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{
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return kStatus_InvalidArgument;
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}
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/* only work with aligned activationCode */
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if (0U != (0x3u & (uintptr_t)activationCode))
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{
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return kStatus_InvalidArgument;
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}
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activationCodeAligned = (uint32_t *)(uintptr_t)activationCode;
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/* check if ENROLL is allowed */
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if (0x0u == (base->ALLOW & PUF_ALLOW_ALLOWENROLL_MASK))
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{
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return kStatus_EnrollNotAllowed;
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}
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/* begin */
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base->CTRL = PUF_CTRL_ENROLL_MASK;
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/* check status */
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while (0U == (base->STAT & (PUF_STAT_BUSY_MASK | PUF_STAT_ERROR_MASK)))
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{
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}
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/* read out AC */
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while (0U != (base->STAT & PUF_STAT_BUSY_MASK))
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{
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if (0U != (PUF_STAT_CODEOUTAVAIL_MASK & base->STAT))
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{
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temp32 = base->CODEOUTPUT;
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if (activationCodeSize >= sizeof(uint32_t))
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{
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*activationCodeAligned = temp32;
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activationCodeAligned++;
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activationCodeSize -= sizeof(uint32_t);
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}
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}
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}
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if (((base->STAT & PUF_STAT_SUCCESS_MASK) != 0U) && (activationCodeSize == 0U))
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{
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status = kStatus_Success;
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}
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return status;
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}
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/*!
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* brief Start PUF
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*
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* The Activation Code generated during the Enroll operation is used to
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* reconstruct the digital fingerprint. This needs to be done after every power-up
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* and reset.
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*
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* param base PUF peripheral base address
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||
|
* param activationCode Word aligned address of the input activation code.
|
||
|
* param activationCodeSize Size of the activationCode buffer in bytes. Shall be 1192 bytes.
|
||
|
* return Status of start operation.
|
||
|
*/
|
||
|
status_t PUF_Start(PUF_Type *base, const uint8_t *activationCode, size_t activationCodeSize)
|
||
|
{
|
||
|
status_t status = kStatus_Fail;
|
||
|
const uint32_t *activationCodeAligned = NULL;
|
||
|
register uint32_t temp32 = 0;
|
||
|
|
||
|
/* check that activation code size is at least 1192 bytes */
|
||
|
if (activationCodeSize < 1192U)
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
/* only work with aligned activationCode */
|
||
|
if (0U != (0x3u & (uintptr_t)activationCode))
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
activationCodeAligned = (const uint32_t *)(uintptr_t)activationCode;
|
||
|
|
||
|
/* check if START is allowed */
|
||
|
if (0x0u == (base->ALLOW & PUF_ALLOW_ALLOWSTART_MASK))
|
||
|
{
|
||
|
return kStatus_StartNotAllowed;
|
||
|
}
|
||
|
|
||
|
/* begin */
|
||
|
base->CTRL = PUF_CTRL_START_MASK;
|
||
|
|
||
|
/* check status */
|
||
|
while (0U == (base->STAT & (PUF_STAT_BUSY_MASK | PUF_STAT_ERROR_MASK)))
|
||
|
{
|
||
|
}
|
||
|
|
||
|
/* while busy send AC */
|
||
|
while (0U != (base->STAT & PUF_STAT_BUSY_MASK))
|
||
|
{
|
||
|
if (0U != (PUF_STAT_CODEINREQ_MASK & base->STAT))
|
||
|
{
|
||
|
if (activationCodeSize >= sizeof(uint32_t))
|
||
|
{
|
||
|
temp32 = *activationCodeAligned;
|
||
|
activationCodeAligned++;
|
||
|
activationCodeSize -= sizeof(uint32_t);
|
||
|
}
|
||
|
base->CODEINPUT = temp32;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* get status */
|
||
|
if (0U != (base->STAT & PUF_STAT_SUCCESS_MASK))
|
||
|
{
|
||
|
status = kStatus_Success;
|
||
|
}
|
||
|
|
||
|
return status;
|
||
|
}
|
||
|
|
||
|
/*!
|
||
|
* brief Set intrinsic key
|
||
|
*
|
||
|
* The digital fingerprint generated during the Enroll/Start
|
||
|
* operations is used to generate a Key Code (KC) that defines a unique intrinsic
|
||
|
* key. This KC is returned to be stored in an NVM or a file. This operation
|
||
|
* needs to be done only once for each intrinsic key.
|
||
|
* Each time a Set Intrinsic Key operation is executed a new unique key is
|
||
|
* generated.
|
||
|
*
|
||
|
* param base PUF peripheral base address
|
||
|
* param keyIndex PUF key index register
|
||
|
* param keySize Size of the intrinsic key to generate in bytes.
|
||
|
* param[out] keyCode Word aligned address of the resulting key code.
|
||
|
* param keyCodeSize Size of the keyCode buffer in bytes. Shall be PUF_GET_KEY_CODE_SIZE_FOR_KEY_SIZE(keySize).
|
||
|
* return Status of set intrinsic key operation.
|
||
|
*/
|
||
|
status_t PUF_SetIntrinsicKey(
|
||
|
PUF_Type *base, puf_key_index_register_t keyIndex, size_t keySize, uint8_t *keyCode, size_t keyCodeSize)
|
||
|
{
|
||
|
status_t status = kStatus_Fail;
|
||
|
uint32_t *keyCodeAligned = NULL;
|
||
|
register uint32_t temp32 = 0;
|
||
|
|
||
|
/* check if SET KEY is allowed */
|
||
|
if (0x0u == (base->ALLOW & PUF_ALLOW_ALLOWSETKEY_MASK))
|
||
|
{
|
||
|
return kStatus_Fail;
|
||
|
}
|
||
|
|
||
|
/* only work with aligned keyCode */
|
||
|
if (0U != (0x3u & (uintptr_t)keyCode))
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
/* Check that keySize is in the correct range and that it is multiple of 8 */
|
||
|
if ((keySize < (uint32_t)kPUF_KeySizeMin) || (keySize > (uint32_t)kPUF_KeySizeMax) || (0U != (keySize & 0x7U)))
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
/* check that keyCodeSize is correct for given keySize */
|
||
|
if (keyCodeSize < PUF_GET_KEY_CODE_SIZE_FOR_KEY_SIZE(keySize))
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
if ((uint32_t)keyIndex > (uint32_t)kPUF_KeyIndexMax)
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
keyCodeAligned = (uint32_t *)(uintptr_t)keyCode;
|
||
|
|
||
|
/* program the key size and index */
|
||
|
base->KEYSIZE = keySize >> 3;
|
||
|
base->KEYINDEX = (uint32_t)keyIndex;
|
||
|
|
||
|
/* begin */
|
||
|
base->CTRL = PUF_CTRL_GENERATEKEY_MASK;
|
||
|
|
||
|
/* wait till command is accepted */
|
||
|
while (0U == (base->STAT & (PUF_STAT_BUSY_MASK | PUF_STAT_ERROR_MASK)))
|
||
|
{
|
||
|
}
|
||
|
|
||
|
/* while busy read KC */
|
||
|
while (0U != (base->STAT & PUF_STAT_BUSY_MASK))
|
||
|
{
|
||
|
if (0U != (PUF_STAT_CODEOUTAVAIL_MASK & base->STAT))
|
||
|
{
|
||
|
temp32 = base->CODEOUTPUT;
|
||
|
if (keyCodeSize >= sizeof(uint32_t))
|
||
|
{
|
||
|
*keyCodeAligned = temp32;
|
||
|
keyCodeAligned++;
|
||
|
keyCodeSize -= sizeof(uint32_t);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* get status */
|
||
|
if (0U != (base->STAT & PUF_STAT_SUCCESS_MASK))
|
||
|
{
|
||
|
status = kStatus_Success;
|
||
|
}
|
||
|
|
||
|
return status;
|
||
|
}
|
||
|
|
||
|
/*!
|
||
|
* brief Set user key
|
||
|
*
|
||
|
* The digital fingerprint generated during the Enroll/Start
|
||
|
* operations and a user key (UK) provided as input are used to
|
||
|
* generate a Key Code (KC). This KC is sent returned to be stored
|
||
|
* in an NVM or a file. This operation needs to be done only once for each user key.
|
||
|
*
|
||
|
* param base PUF peripheral base address
|
||
|
* param keyIndex PUF key index register
|
||
|
* param userKey Word aligned address of input user key.
|
||
|
* param userKeySize Size of the input user key in bytes.
|
||
|
* param[out] keyCode Word aligned address of the resulting key code.
|
||
|
* param keyCodeSize Size of the keyCode buffer in bytes. Shall be PUF_GET_KEY_CODE_SIZE_FOR_KEY_SIZE(userKeySize).
|
||
|
* return Status of set user key operation.
|
||
|
*/
|
||
|
status_t PUF_SetUserKey(PUF_Type *base,
|
||
|
puf_key_index_register_t keyIndex,
|
||
|
const uint8_t *userKey,
|
||
|
size_t userKeySize,
|
||
|
uint8_t *keyCode,
|
||
|
size_t keyCodeSize)
|
||
|
{
|
||
|
status_t status = kStatus_Fail;
|
||
|
uint32_t *keyCodeAligned = NULL;
|
||
|
const uint32_t *userKeyAligned = NULL;
|
||
|
register uint32_t temp32 = 0;
|
||
|
|
||
|
/* check if SET KEY is allowed */
|
||
|
if (0x0u == (base->ALLOW & PUF_ALLOW_ALLOWSETKEY_MASK))
|
||
|
{
|
||
|
return kStatus_Fail;
|
||
|
}
|
||
|
|
||
|
/* only work with aligned keyCode */
|
||
|
if (0U != (0x3u & (uintptr_t)keyCode))
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
/* Check that userKeySize is in the correct range and that it is multiple of 8 */
|
||
|
if ((userKeySize < (uint32_t)kPUF_KeySizeMin) || (userKeySize > (uint32_t)kPUF_KeySizeMax) ||
|
||
|
(0U != (userKeySize & 0x7U)))
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
/* check that keyCodeSize is correct for given userKeySize */
|
||
|
if (keyCodeSize < PUF_GET_KEY_CODE_SIZE_FOR_KEY_SIZE(userKeySize))
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
if ((uint32_t)keyIndex > (uint32_t)kPUF_KeyIndexMax)
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
keyCodeAligned = (uint32_t *)(uintptr_t)keyCode;
|
||
|
userKeyAligned = (const uint32_t *)(uintptr_t)userKey;
|
||
|
|
||
|
/* program the key size and index */
|
||
|
base->KEYSIZE = userKeySize >> 3; /* convert to 64-bit blocks */
|
||
|
base->KEYINDEX = (uint32_t)keyIndex;
|
||
|
|
||
|
/* We have to store the user key on index 0 swaped for HW bus */
|
||
|
if (keyIndex == kPUF_KeyIndex_00)
|
||
|
{
|
||
|
userKeyAligned = userKeyAligned + (userKeySize / sizeof(uint32_t));
|
||
|
}
|
||
|
|
||
|
/* begin */
|
||
|
base->CTRL = PUF_CTRL_SETKEY_MASK;
|
||
|
|
||
|
/* wait till command is accepted */
|
||
|
while (0U == (base->STAT & (PUF_STAT_BUSY_MASK | PUF_STAT_ERROR_MASK)))
|
||
|
{
|
||
|
}
|
||
|
|
||
|
/* while busy write UK and read KC */
|
||
|
while (0U != (base->STAT & PUF_STAT_BUSY_MASK))
|
||
|
{
|
||
|
if (0U != (PUF_STAT_KEYINREQ_MASK & base->STAT))
|
||
|
{
|
||
|
if (userKeySize >= sizeof(uint32_t))
|
||
|
{
|
||
|
#if defined(LPC54S018_SERIES)
|
||
|
if (keyIndex == kPUF_KeyIndex_00)
|
||
|
{
|
||
|
userKeyAligned--;
|
||
|
temp32 = *userKeyAligned;
|
||
|
userKeySize -= sizeof(uint32_t);
|
||
|
}
|
||
|
#else
|
||
|
if (keyIndex == kPUF_KeyIndex_00)
|
||
|
{
|
||
|
userKeyAligned--;
|
||
|
temp32 = __REV(*userKeyAligned);
|
||
|
userKeySize--;
|
||
|
}
|
||
|
#endif /* defined(LPC54S018_SERIES) */
|
||
|
else if (keyIndex != kPUF_KeyIndex_00)
|
||
|
{
|
||
|
temp32 = *userKeyAligned;
|
||
|
userKeyAligned++;
|
||
|
userKeySize -= sizeof(uint32_t);
|
||
|
}
|
||
|
else
|
||
|
{
|
||
|
/* Intentional empty */
|
||
|
}
|
||
|
}
|
||
|
base->KEYINPUT = temp32;
|
||
|
}
|
||
|
|
||
|
if (0U != (PUF_STAT_CODEOUTAVAIL_MASK & base->STAT))
|
||
|
{
|
||
|
temp32 = base->CODEOUTPUT;
|
||
|
if (keyCodeSize >= sizeof(uint32_t))
|
||
|
{
|
||
|
*keyCodeAligned = temp32;
|
||
|
keyCodeAligned++;
|
||
|
keyCodeSize -= sizeof(uint32_t);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* get status */
|
||
|
if (0U != (base->STAT & PUF_STAT_SUCCESS_MASK))
|
||
|
{
|
||
|
status = kStatus_Success;
|
||
|
}
|
||
|
|
||
|
return status;
|
||
|
}
|
||
|
|
||
|
static status_t puf_getHwKey(PUF_Type *base, const uint8_t *keyCode, size_t keyCodeSize)
|
||
|
{
|
||
|
status_t status = kStatus_Fail;
|
||
|
uint32_t *keyCodeAligned = NULL;
|
||
|
register uint32_t temp32 = 0;
|
||
|
|
||
|
keyCodeAligned = (uint32_t *)(uintptr_t)keyCode;
|
||
|
|
||
|
/* begin */
|
||
|
base->CTRL = PUF_CTRL_GETKEY_MASK;
|
||
|
|
||
|
/* wait till command is accepted */
|
||
|
while (0U == (base->STAT & (PUF_STAT_BUSY_MASK | PUF_STAT_ERROR_MASK)))
|
||
|
{
|
||
|
}
|
||
|
|
||
|
/* while busy send KC, key is reconstructed to HW bus */
|
||
|
while (0U != (base->STAT & PUF_STAT_BUSY_MASK))
|
||
|
{
|
||
|
if (0U != (PUF_STAT_CODEINREQ_MASK & base->STAT))
|
||
|
{
|
||
|
if (keyCodeSize >= sizeof(uint32_t))
|
||
|
{
|
||
|
temp32 = *keyCodeAligned;
|
||
|
keyCodeAligned++;
|
||
|
keyCodeSize -= sizeof(uint32_t);
|
||
|
}
|
||
|
base->CODEINPUT = temp32;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* get status */
|
||
|
if (0U != (base->STAT & PUF_STAT_SUCCESS_MASK))
|
||
|
{
|
||
|
status = kStatus_Success;
|
||
|
}
|
||
|
|
||
|
return status;
|
||
|
}
|
||
|
|
||
|
/*!
|
||
|
* brief Reconstruct hw bus key from a key code
|
||
|
*
|
||
|
* The digital fingerprint generated during the Start operation and the KC
|
||
|
* generated during a Set Key operation (Set intrinsic key or Set user key) are used to retrieve a stored key. This
|
||
|
* operation needs to be done every time a key is needed.
|
||
|
* This function accepts only Key Codes created for PUF index register kPUF_KeyIndex_00.
|
||
|
* Such a key is output directly to a dedicated hardware bus. The reconstructed key is not exposed to system memory.
|
||
|
*
|
||
|
* param base PUF peripheral base address
|
||
|
* param keyCode Word aligned address of the input key code.
|
||
|
* param keyCodeSize Size of the keyCode buffer in bytes. Shall be PUF_GET_KEY_CODE_SIZE_FOR_KEY_SIZE(keySize).
|
||
|
* param keySlot key slot to output on hw bus. Parameter is ignored on devices with less than two key slots.
|
||
|
* param keyMask key masking value. Shall be random for each POR/reset. Value does not have to be cryptographicaly
|
||
|
* secure.
|
||
|
* return Status of get key operation.
|
||
|
*/
|
||
|
status_t PUF_GetHwKey(
|
||
|
PUF_Type *base, const uint8_t *keyCode, size_t keyCodeSize, puf_key_slot_t keySlot, uint32_t keyMask)
|
||
|
{
|
||
|
status_t status = kStatus_Fail;
|
||
|
uint32_t keyIndex;
|
||
|
|
||
|
/* check if GET KEY is allowed */
|
||
|
if (0x0u == (base->ALLOW & PUF_ALLOW_ALLOWGETKEY_MASK))
|
||
|
{
|
||
|
return kStatus_Fail;
|
||
|
}
|
||
|
|
||
|
/* only work with aligned keyCode */
|
||
|
if (0U != (0x3u & (uintptr_t)keyCode))
|
||
|
{
|
||
|
return kStatus_Fail;
|
||
|
}
|
||
|
|
||
|
/* check that keyCodeSize is at least PUF_MIN_KEY_CODE_SIZE */
|
||
|
if (keyCodeSize < PUF_MIN_KEY_CODE_SIZE)
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
keyIndex = (uint32_t)(0x0Fu & (uint32_t)keyCode[1]);
|
||
|
|
||
|
/* check the Key Code header byte 1. index must be zero for the hw key. */
|
||
|
if (kPUF_KeyIndex_00 != (puf_key_index_register_t)keyIndex)
|
||
|
{
|
||
|
return kStatus_Fail;
|
||
|
}
|
||
|
|
||
|
#if defined(PUF_KEYMASK_COUNT) && (PUF_KEYMASK_COUNT > 0)
|
||
|
volatile uint32_t *keyMask_reg = NULL;
|
||
|
uint32_t regVal = ((uint32_t)2U << ((uint32_t)2U * (uint32_t)keySlot));
|
||
|
|
||
|
switch (keySlot)
|
||
|
{
|
||
|
case kPUF_KeySlot0:
|
||
|
keyMask_reg = &base->KEYMASK[0];
|
||
|
break;
|
||
|
|
||
|
case kPUF_KeySlot1:
|
||
|
keyMask_reg = &base->KEYMASK[1];
|
||
|
break;
|
||
|
#if (PUF_KEYMASK_COUNT > 2)
|
||
|
case kPUF_KeySlot2:
|
||
|
keyMask_reg = &base->KEYMASK[2];
|
||
|
break;
|
||
|
|
||
|
case kPUF_KeySlot3:
|
||
|
keyMask_reg = &base->KEYMASK[3];
|
||
|
break;
|
||
|
#endif /* PUF_KEYMASK_COUNT > 2 */
|
||
|
default:
|
||
|
status = kStatus_InvalidArgument;
|
||
|
break;
|
||
|
}
|
||
|
#endif /* PUF_KEYMASK_COUNT */
|
||
|
|
||
|
if (status != kStatus_InvalidArgument)
|
||
|
{
|
||
|
#if defined(PUF_KEYMASK_COUNT) && (PUF_KEYMASK_COUNT > 0)
|
||
|
base->KEYRESET = regVal;
|
||
|
base->KEYENABLE = regVal;
|
||
|
*keyMask_reg = keyMask;
|
||
|
#endif /* FSL_FEATURE_PUF_HAS_KEYSLOTS */
|
||
|
|
||
|
status = puf_getHwKey(base, keyCode, keyCodeSize);
|
||
|
|
||
|
#if defined(FSL_FEATURE_PUF_HAS_SHIFT_STATUS) && (FSL_FEATURE_PUF_HAS_SHIFT_STATUS > 0)
|
||
|
size_t keyWords = 0;
|
||
|
|
||
|
if (status == kStatus_Success)
|
||
|
{
|
||
|
/* if the corresponding shift count does not match, return fail anyway */
|
||
|
keyWords = ((((size_t)keyCode[3]) * 2U) - 1u) << ((size_t)keySlot << 2U);
|
||
|
if (keyWords != ((0x0FUL << ((uint32_t)keySlot << 2U)) & base->SHIFT_STATUS))
|
||
|
{
|
||
|
status = kStatus_Fail;
|
||
|
}
|
||
|
}
|
||
|
#elif defined(PUF_IDXBLK_SHIFT_IND_KEY0_MASK) && PUF_IDXBLK_SHIFT_IND_KEY0_MASK
|
||
|
size_t keyWords = 0;
|
||
|
|
||
|
if (status == kStatus_Success)
|
||
|
{
|
||
|
/* if the corresponding shift count does not match, return fail anyway */
|
||
|
keyWords = ((((size_t)keyCode[3]) * 2U) - 1u) << ((size_t)keySlot << 2U);
|
||
|
if (keyWords != ((0x0FUL << ((uint32_t)keySlot << 2U)) & base->IDXBLK_SHIFT))
|
||
|
{
|
||
|
status = kStatus_Fail;
|
||
|
}
|
||
|
}
|
||
|
#endif /* FSL_FEATURE_PUF_HAS_SHIFT_STATUS || PUF_IDXBLK_SHIFT_IND_KEY0_MASK */
|
||
|
}
|
||
|
|
||
|
return status;
|
||
|
}
|
||
|
|
||
|
/*!
|
||
|
* brief Checks if Get Key operation is allowed.
|
||
|
*
|
||
|
* This function returns true if get key operation is allowed.
|
||
|
*
|
||
|
* param base PUF peripheral base address
|
||
|
* return true if get key operation is allowed
|
||
|
*/
|
||
|
bool PUF_IsGetKeyAllowed(PUF_Type *base)
|
||
|
{
|
||
|
/* check if GET KEY is allowed */
|
||
|
if (0x0u == (base->ALLOW & PUF_ALLOW_ALLOWGETKEY_MASK))
|
||
|
{
|
||
|
return false;
|
||
|
}
|
||
|
|
||
|
return true;
|
||
|
}
|
||
|
|
||
|
/*!
|
||
|
* brief Reconstruct key from a key code
|
||
|
*
|
||
|
* The digital fingerprint generated during the Start operation and the KC
|
||
|
* generated during a Set Key operation (Set intrinsic key or Set user key) are used to retrieve a stored key. This
|
||
|
* operation needs to be done every time a key is needed.
|
||
|
* This function accepts only Key Codes created for PUF index registers kPUF_KeyIndex_01 to kPUF_KeyIndex_15.
|
||
|
*
|
||
|
* param base PUF peripheral base address
|
||
|
* param keyCode Word aligned address of the input key code.
|
||
|
* param keyCodeSize Size of the keyCode buffer in bytes. Shall be PUF_GET_KEY_CODE_SIZE_FOR_KEY_SIZE(keySize).
|
||
|
* param[out] key Word aligned address of output key.
|
||
|
* param keySize Size of the output key in bytes.
|
||
|
* return Status of get key operation.
|
||
|
*/
|
||
|
status_t PUF_GetKey(PUF_Type *base, const uint8_t *keyCode, size_t keyCodeSize, uint8_t *key, size_t keySize)
|
||
|
{
|
||
|
status_t status = kStatus_Fail;
|
||
|
uint32_t *keyCodeAligned = NULL;
|
||
|
uint32_t *keyAligned = NULL;
|
||
|
uint32_t keyIndex;
|
||
|
register uint32_t temp32 = 0;
|
||
|
|
||
|
/* check if GET KEY is allowed */
|
||
|
if (0x0u == (base->ALLOW & PUF_ALLOW_ALLOWGETKEY_MASK))
|
||
|
{
|
||
|
return kStatus_Fail;
|
||
|
}
|
||
|
|
||
|
/* only work with aligned keyCode */
|
||
|
if (0U != (0x3u & (uintptr_t)keyCode))
|
||
|
{
|
||
|
return kStatus_Fail;
|
||
|
}
|
||
|
|
||
|
/* only work with aligned key */
|
||
|
if (0U != (0x3u & (uintptr_t)key))
|
||
|
{
|
||
|
return kStatus_Fail;
|
||
|
}
|
||
|
|
||
|
/* check that keyCodeSize is correct for given keySize */
|
||
|
if (keyCodeSize < PUF_GET_KEY_CODE_SIZE_FOR_KEY_SIZE(keySize))
|
||
|
{
|
||
|
return kStatus_InvalidArgument;
|
||
|
}
|
||
|
|
||
|
keyIndex = (0x0Fu & (uint32_t)keyCode[1]);
|
||
|
|
||
|
/* check the Key Code header byte 1. index must be non-zero for the register key. */
|
||
|
if (kPUF_KeyIndex_00 == (puf_key_index_register_t)keyIndex)
|
||
|
{
|
||
|
return kStatus_Fail;
|
||
|
}
|
||
|
|
||
|
keyCodeAligned = (uint32_t *)(uintptr_t)keyCode;
|
||
|
keyAligned = (uint32_t *)(uintptr_t)key;
|
||
|
|
||
|
/* begin */
|
||
|
base->CTRL = PUF_CTRL_GETKEY_MASK;
|
||
|
|
||
|
/* wait till command is accepted */
|
||
|
while (0U == (base->STAT & (PUF_STAT_BUSY_MASK | PUF_STAT_ERROR_MASK)))
|
||
|
{
|
||
|
}
|
||
|
|
||
|
/* while busy send KC, read key */
|
||
|
while (0U != (base->STAT & PUF_STAT_BUSY_MASK))
|
||
|
{
|
||
|
if (0U != (PUF_STAT_CODEINREQ_MASK & base->STAT))
|
||
|
{
|
||
|
temp32 = 0;
|
||
|
if (keyCodeSize >= sizeof(uint32_t))
|
||
|
{
|
||
|
temp32 = *keyCodeAligned;
|
||
|
keyCodeAligned++;
|
||
|
keyCodeSize -= sizeof(uint32_t);
|
||
|
}
|
||
|
base->CODEINPUT = temp32;
|
||
|
}
|
||
|
|
||
|
if (0U != (PUF_STAT_KEYOUTAVAIL_MASK & base->STAT))
|
||
|
{
|
||
|
keyIndex = base->KEYOUTINDEX;
|
||
|
temp32 = base->KEYOUTPUT;
|
||
|
if (keySize >= sizeof(uint32_t))
|
||
|
{
|
||
|
*keyAligned = temp32;
|
||
|
keyAligned++;
|
||
|
keySize -= sizeof(uint32_t);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* get status */
|
||
|
if ((keyIndex != 0U) && (0U != (base->STAT & PUF_STAT_SUCCESS_MASK)))
|
||
|
{
|
||
|
status = kStatus_Success;
|
||
|
}
|
||
|
|
||
|
return status;
|
||
|
}
|
||
|
|
||
|
/*!
|
||
|
* brief Zeroize PUF
|
||
|
*
|
||
|
* This function clears all PUF internal logic and puts the PUF to error state.
|
||
|
*
|
||
|
* param base PUF peripheral base address
|
||
|
* return Status of the zeroize operation.
|
||
|
*/
|
||
|
status_t PUF_Zeroize(PUF_Type *base)
|
||
|
{
|
||
|
status_t status = kStatus_Fail;
|
||
|
|
||
|
/* zeroize command is always allowed */
|
||
|
base->CTRL = PUF_CTRL_ZEROIZE_MASK;
|
||
|
|
||
|
/* check that command is accepted */
|
||
|
if ((0U != (base->STAT & PUF_STAT_ERROR_MASK)) && (0U == base->ALLOW))
|
||
|
{
|
||
|
status = kStatus_Success;
|
||
|
}
|
||
|
|
||
|
return status;
|
||
|
}
|